1. Field of Invention
This invention relates generally to an improvement in diagnostic medical ultrasound imaging, and more specifically to a system and method for integrating a diagnostic medical ultrasound transducer probe with a body-tissue parameter measurement mechanism for examination of body-tissue, in conjunction with diagnostic ultrasound imaging.
2. Description of the Prior Art
There is growing interest in 2-D and 3-D ultrasound imaging for diagnostic medical applications. Commonly available ultrasound systems for medical applications include ultrasound imaging probes with one or more one-dimensional (1-D) ultrasound transducer arrays for obtaining 2-D images of body-tissue. Such ultrasound imaging probes are designed exclusively for passive ultrasound imaging. Subtle differences in ultrasound images of body-tissue are used to detect the presence of undesirable body-tissue, such as tumors. Sometimes the acoustic impedance contrast between healthy and undesirable body-tissue is too small for detection by ultrasound imaging alone.
Alternatively, undesirable body-tissue can frequently be detected by manual palpation, such as by physical examination of breast or prostate tissue for hard lumps or lesions. Unfortunately, manual palpation is not very quantitative nor repeatable, and the feel of a tumor varies greatly with its depth from the body-tissue surface. Thus, the sensitivity of detecting undesirable body-tissue by the nonquantitative manual palpation of body-tissue alone is limited.
In order to solve these palpation sensitivity and quantification problems, there has been discussion of using force-sensing mechanisms for breast and rectal prostate exams. For example, the use of a Tekscan(trademark) 2-D planar piezoresistive force sensing array for prostate exams is discussed in an article entitled xe2x80x9cCorrelation of Mechanical Imaging and Histopathology of Radical Prostatectomy Specimens: A Pilot Study for Detecting Prostate Cancer,xe2x80x9d by P. Niemczyk et al., Journal of Urology, Vol. 160, pp. 1-5, September 1998. Furthermore, a BreastCheck(trademark) handheld mapping device with a pressure-sensing array for detection of breast nodules, made by the Assurance Medical Division of UroMed Corporation, located in Hopkinton, Mass., is undergoing clinical testing.
But there has been no disclosure of body-tissue palpation or other parameter measurement mechanisms integrated within or attached to ultrasound imaging probes for body-tissue parameter measurement in combination with 2-D or 3-D ultrasound imaging. Complementary examination of body-tissue by sequential (or simultaneous) use of ultrasound imaging and body-tissue palpation or other parameter measurement could provide more sensitivity in detecting undesirable body-tissue. Furthermore, the above references do not address the more difficult problem of sensing deeper tumors using body-tissue surface force-sensing mechanisms.
What is needed is a system, method, and probe to obtain 2-D or 3-D ultrasound images of body-tissues in combination with coregistered or overlaid software or hardware controlled body-tissue parameter measurements. The ultrasound system and method should be relatively low in cost and permit efficient examination and identification of tumors and other undesirable body-tissues. Ideally, body-tissue parameter measurement should allow for the application of static or dynamic body-tissue loading at any point on or in the body-tissue surface or depth, as well as the direct sensing of body-tissue surface parameters.
One object of the present invention is to provide a system, method, and probe to obtain 2-D or 3-D ultrasound images of body-tissues in combination with software or hardware controlled body-tissue parameter measurement. For 3-D imaging using principal imaging and secondary motion-tracking transducers, the principal and secondary imaging information needs to be provided concurrently, such that the secondary imaging information can be used to estimate the movement of the transducer probe and/or the body-tissue between respective image data frames.
Another object of the invention is to provide a relatively low cost ultrasound system, method, and probe to permit efficient examination and identification of tumors and other undesirable body-tissues.
The invention is directed to a medical diagnostic ultrasound probe, including one or more ultrasound imaging transducer elements and a body-tissue parameter measurement mechanism.